The proposed work involves the biological testing of a new derivative of 7,12-dimethylbenz(a)anthracene and the synthesis of other compounds which are potential metabolites of this carcinogen. The newly acquired 7,12-dimethylbenz(a)anthracene-3-,9-diol will be tested for estrogenic character by bioassay. The binding of this potential estradiol inhibitor to the estrogen receptor protein will also be carried out. Finally, the possible carcinogenic potential of this compound will be assessed and compared with that of DMBA, BA, and BA-3,9-diol. The study of the biochemical reactions of 7,12-dimethylbenz(a)anthracene-7,8-dihydrodiol are also being studied; in particular, the formation of this type of compound in the breast tissue of the rat.